Method of using a level

ABSTRACT

A water or spirit level is composed of an elongated body, preferably of metal, at least one bubble mounted in the elongated body, and end caps, preferably of plastics material, at the end faces of the elongated body, wherein at least one outer surface of the elongated body constitutes a preferred measuring surface. At least one of the end caps is releasably connected to the level body such that the end cap can optionally be removed and once again replaced.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of U.S. patent applicationSer. No. 10/376,462, filed Feb. 28, 2003.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method of using a water or spirit levelcomposed of an elongated body, preferably of metal, at least one bubblemounted in the elongated body, and end caps, preferably of plasticsmaterial, at the end faces of the elongated body, wherein at least oneouter surface of the elongated body constitutes a preferred measuringsurface.

2. Description of the Related Art

Levels have been for decades manufactured all over the world in largenumbers and are used regularly primarily in civil engineering. Forreasons of strength and dimensional stability, the body of a level isusually composed of metal, in most cases light metal, and conventionallyhas a rectangular hollow cross section or a I-shaped solid crosssection. In order to prevent damage to the levels in case of impacts orwhen dropped, the level body is provided with end caps which arecomposed of a relatively soft, elastic, shock-absorbing material,usually plastics material. When the level body is of a hollow section,the end caps also serve as closures.

A level with an end cap of plastics material is disclosed, for example,in AT 398 846 B. This level has a level body with an I-shaped crosssection. The cross section of the end caps is rectangular and theirdimensions are adapted to the dimensions of the level body. Forfastening the end caps to the level body, the end faces of the levelbody are provided with two blind-end openings which have severalundercuts. The end caps are provided with appropriate lugs which engagepositively in the blind-end openings. In this manner, the end caps areinseparably fastened to the level body.

In the manufacture of levels, there is the tendency to construct theshock absorbers at the end caps larger and larger in order to achieve abetter protection against damage. However, end caps which aremanufactured as injection molded articles have manufacturing tolerancesand also have a different coefficient of expansion than the level body.In order to prevent the end caps from projecting beyond the measuringsurfaces of the level, the end caps are manufactured with smaller crosssectional dimensions than the level bodies; in addition, also foraesthetic reasons, the end caps are frequently slightly outwardlyconically beveled. The smaller cross sectional dimensions result in anundesirable step in the plane of the measuring surface in the joiningarea between the end cap and the level body.

This has the result that, for example, in the corner area of two wallswhere a line or marking has to be transferred from one wall to theother, the line or marking cannot be continued precisely around thecorner because the measuring surface of the level cannot be placed allthe way into the corner because of the presence of the end cap mountedon the end face of the level body. The greater the length of the portionwith no line or marking, the more effective the shock absorption of theend cap. This results in inaccuracies.

Many artisans solve this problem by pulling off the end cap by applyinggreat force. However, since the end caps are not designed for such ause, they find no support when they are once again inserted into thelevel body; rather, the end caps remain separate and become lost. Thisis not satisfactory.

SUMMARY OF THE INVENTION

Therefore, it is the primary object of the present invention to providea method of using a level which makes it possible to continue lines ormarkings precisely around the corner without problems, without giving upthe impact protection.

In accordance with the present invention, the method comprises, fortransferring the line or marking away from the corner onto the walls,inserting the cap in the level body, and, for continuing the line ormarking in the corner, removing one of the end caps from the level bodyso as to expose an end face thereof, and placing the end face of thelevel body into the corner from each side of the corner.

The basic concept of the level resides in constructing the connectionbetween an end cap and the level body so as to be releasable, so thatthe end cap can be optionally removed and replaced again. On the onehand, the connection between the end cap and the level body must becapable of absorbing a sufficient force in order to prevent anunintentional separation of the end cap in the case of impacts; on theother hand, it should be possible for the user to quickly and easilyremove the end cap as required and, of course, to place it back onto thelevel body.

In accordance with a preferred feature of the level, a locking device inthe form of a resiliently mounted locking knob is provided on the shaftof the end cap with which the end cap is connected to the end face ofthe level body, wherein the locking knob extends into or through anindentation or opening provided at the appropriate location in the wallof the level body. Since the locking knob is resiliently fastened to theshaft, the locking knob can be resiliently inserted by applying acompressive force.

The locking knob is inserted when the end cap is mounted on the levelbody, however, when the indentation or opening in the wall of the levelbody is reached, the locking knob jumps out and ensures with its outersurface a locking action relative to the wall of the indentation oropening. By pressing in the locking knob, which advantageously isarranged on two oppositely located sides of the level body, the lockingaction can be released, so that the end cap can be pulled off.

While the use of the locking knob is the preferred solution, which hasthe advantage that no tool is required for its actuation, there areother embodiments of locking means, for example, by clamping screws oralso locking means which act like bayonet closures, or also magneticlocking means.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of the disclosure. For a better understanding of the invention, itsoperating advantages, specific objects attained by its use, referenceshould be had to the drawing and descriptive matter in which there areillustrated and described preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing:

FIG. 1 is a side view of a first embodiment of the level according tothe present invention, shown with a portion of the wall of the levelbody broken away;

FIG. 2 is a side view of an end cap to be mounted on the level of FIG.1;

FIG. 3 is a sectional view taken along sectional line III-III of FIG. 1;

FIG. 4 is a perspective view of the end cap;

FIG. 5 is a side view of a second embodiment of the level according tothe present invention;

FIG. 6 is a side view of an end cap to be mounted on the level of FIG.5;

FIG. 7 is a sectional view taken along sectional line VII-VII of FIG. 5;

FIG. 8 is a sectional view taken along sectional line VIII-VIII of FIG.5;

FIG. 9 is a side view of a third embodiment of the level according tothe present invention;

FIG. 10 is a side view of an end cap to be mounted on the level of FIG.9; and

FIG. 11 is a sectional view taken along sectional line XI-XI of FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a side view of a first level 1. The level 1 has an elongatedbody 2 which is constructed as a hollow profile of metal, particularlylight metal, and is provided in the known manner with recesses oropenings 3 and 4 for the insertion of bubbles which extendperpendicularly of each other. Of the end caps 7 arranged on the ends 5,6 at the end faces of the level body 1, the end cap 7 on the left end 5is shown inserted and partially in section, while the end cap 7 on theright end 6 is shown as FIG. 2 still outside of the body 2 shortlybefore being inserted.

The end cap 7, shown in a side view in FIG. 2 and in a perspective viewin FIG. 4, is composed of an end plate 8 whose circumference correspondsapproximately to the cross section of the body 2 and which with itsthickness projects beyond the body 2, and of a hollow shaft 9 connectedto the end plate 8. Together with the inner portion 10 of the end plate8, the hollow shaft 9 is composed of a harder plastics material ofhigher strength because it must ensure the connection between the endcap 7 and the body 2, and an outer part 11 of the end plate 8 which isof a softer plastics material and serves for shock absorption. The endcap 7 can be manufactured in the known manner in a two-componentinjection molding process in order to ensure a permanent connection ofthe parts 10, 11.

The outer dimensions of the hollow shaft 9 are slightly smaller than theinner dimensions of the body 2, so that the end cap 7 can be pushed inthe direction of arrow 12 into the hollow space of the body 2, as seenin FIG. 1. In order to be able to compensate for any tolerances, ribs13, 14 are provided on the outer surfaces of the walls of the shaft 9,wherein the excess dimensions of the ribs are cut off when the end capis pushed in for the first time, so that a secure frictional engagementis ensured. Further details of the end cap 7 can be seen in FIG. 4.

A locking knob 15 each is provided on opposite sides of the wall 23 ofthe shaft 9. The locking knobs 15 each have a circular circumference andform a cylindrical portion 16 which protrudes beyond the surface of therespective shaft wall. Each locking knob 15 is located in an opening 17of the wall 23 of the shaft 9 and is connected to the wall 23 onlythrough two narrow webs 18. The webs 18 are constructed so as to beresilient and twistable, so that the locking knob 15 can be pushed downby applying a pressure onto its surface, wherein the locking knob 15returns into its original position after the pressure is no longerapplied.

Corresponding to the locking knobs 15, openings 19 are provided in theouter wall 21 of the level body 2, wherein, in the inserted state of theend cap 7 shown in FIG. 3, the oppositely located locking knobs 15extend into and fill out the openings 19. The cylindrical outer surface16 of each locking knob 15 then is in contact with the circumference ofthe holes 19, so that the end cap 7 is prevented from being separatedfrom the connection with the body 2 of the level. By exerting acompressive force in the direction of arrows 20, which can be easilyaccomplished by the thumb and index finger of a hand, the locking knobs15 can be pushed down to such an extent that the end cap 7 can be pulledoff the body 2 of the level 1 without being damaged in the direction ofarrow 22 seen in FIG. 3. The reinsertion of the end cap 7 takes place inthe reverse sequence.

FIG. 5 is a side view of a second embodiment of the level 31. The level31 has an elongated body 32 which is constructed as an I-section ofmetal, particularly light metal, and which is provided in the knownmanner with recesses or openings 33, 34 for inserting bubbles whichextend perpendicularly of each other. Of the end caps 37 arranged at theends 35, 36 of the level body 32, the end cap 37 at the end 35 isalready placed on the level body, while the end cap 37 at the right end36 is illustrated as FIG. 6 shortly before being placed on the body 32.

The end cap 37 illustrated in FIG. 6 in a side view is composed of anend plate 38 whose circumference corresponds approximately to the crosssection of the body 32, and of a shaft 37 connected to the end plate 38.

The shaft 39 is composed of two pairs of parallel, oppositely arrangedtongues 42, 44. The distance between the pairs of tongues 42, 44 isadjusted as exactly as possible to the thickness of the wall 41 of thelevel body 32. Arranged between the pairs of tongues 42, 44 is on theside of the pair of tongues 42 a resilient surface 43 which supports theresiliently lowerable projection 45. Further details of the connectionscan be seen in FIGS. 7 and 8 which show sectional views along linesVII-VII and VIII-VIII in FIG. 5.

For locking the end caps 37 to the level body 32, the level body 32 hasopenings 49 into which the projections 45 engage. For releasing the endcaps 37, the artisan presses with a finger on the projection 45 and isable to pull off the end cap 37.

FIG. 9 is a side view of a third level 51. The level 51 has an elongatedbody 32 constructed as an I-section of metal, particularly light metal,and provided with recesses or openings 33, 34 for inserting bubbleswhich extend perpendicularly of each other. Of the end cap 57 arrangedon the ends 35, 36 of the level body 32, the end cap 57 on the left end35 is placed on the level body 32, while the end cap 57 shown in FIG. 10on the right end 36 is still outside of the body 32.

The end cap 57 illustrated in FIG. 10 in a side view is composed of anend plate 58 whose circumference approximately corresponds to the crosssection of the body 32 and which with its thickness protrudes beyond thebody 32, and of a shaft 59 connected to the end plate 58.

The shaft 59 is composed of two parallel, resilient surfaces 63, whereinthe distances between the surfaces 63 is adjusted to the thickness ofthe wall 41 of the level body 32. A projection 65 is integrally formedon each resilient surface 63. Both projections 65 engage in the openings49 in the wall 41 of the level body 32, as can be seen in FIG. 11.

To be able to separate the end cap 57 from the level body 32, the ends64 of the resilient surfaces 63 are

1. A method for transferring a line or marking onto walls of a roomhaving a corner by using the level including an elongated level body, atleast one bubble placed in the level body, an end cap mounted on eachend of the level body, wherein at least one outer surface of the levelbody is a measuring surface, and wherein the level body having at leastone wall arranged to extend between the outer surface and anothersurface substantially parallel to the measuring surface, said end caphaving an end member and a shaft extending along said wall, said shafthaving a wall with a locking knob, said locking knob having an outersurface that protrudes beyond an outer surface of said wall of saidshaft, said locking knob being resiliently connected to said wall ofsaid shaft, said wall of said level body having a through opening forreceiving said locking knob when said end cap is mounted on one of saidends of said level body, said end caps being releasably attached to thelevel body, such that the end cap is selectively removable andinsertable without tools, for transferring the line or marking away fromthe corner onto the walls, inserting the cap in the level body, and, forcontinuing the line or marking in the corner, removing one of the endcaps from the level body so as to expose an end face thereof, andplacing the end face of the level body into the corner from each side ofthe corner
 2. The method according to claim 1, further comprising, forreleasing the end cap from the level body, depressing the locking knobinto the indentation or opening such that the end cap can be pulled fromthe level body.